There have been conventionally known fishing reels including a magnetic sealing mechanism using a magnetic fluid applied to a bearing. For example, Japanese Patent Application Publication No. 2013-110 (the “'110 Publication”) discloses a magnetic fluid sealed bearing wherein the magnetic fluid seal is retained integrally with the bearing such that foreign substances such as seawater, sand, and dust may not adhere to or penetrate into a bearing body which rotatably supports a drive shaft (e.g., a spool shaft rotatably supporting a spool for winding a fishing line, a pinion to be engaged with and disengaged from the spool shaft, or a handle shaft) rotationally driven in accordance with rotational operation of a handle for winding a fishing line (so as to shut out water and dust for maintaining rotational performance of the bearing).
In general, a lubricant such as grease or oil is applied to a driving section of a drive shaft driven in accordance with operation of the handle for winding a fishing line. Such a lubricant may unfavorably adhere to or penetrate into the magnetic sealing section of the magnetic fluid sealed bearing. The lubricant tends to adhere to or penetrate into a bearing particularly on a pinion which moves in axial directions upon switching operation for switching a clutch mechanism between a clutch-on state wherein a rotational drive force of the handle is transmitted to a spool via a drive gear and the pinion and a clutch-off state wherein the drive force transmission state is canceled and the spool rotates freely. That is, a grease is normally applied to teeth of the pinion meshing with the drive gear; therefore, when the pinion moves in axial directions upon the switching operation of the clutch mechanism, an oil separated from the grease applied to the teeth of the pinion moves in axial directions and penetrates into the magnetic fluid sealed bearing rotatably supporting the pinion so as to degrade the magnetic fluid.
In the magnetic fluid sealed bearing disclosed in the '110 Publication wherein a magnetic fluid seal is disposed adjacent to a side of the bearing body, an O-ring is used to seal the bearing on the side of the magnetic fluid seal not magnetically sealed (the side opposite to the side where the magnetic fluid is retained); therefore, the magnetic sealing section tends to move, and the magnetic fluid seal does not integrate well with the bearing body, resulting in degraded built-in work efficiency and the maintenance efficiency of the bearing. If the magnetic fluid seal is disposed in the bearing, the bearing can be treated more easily. However, foreign substances such as seawater and dust tend to penetrate into the bearing through the outer circumference of the outer ring or the inner ring of the bearing body, degrading the corrosion resistance.